Assuming your feeding your dog things he/she can eat, is there anything wrong with going away from commercial dog food and just feeding your dog say, cooked potatoes and carrots? I want my dog to live a long life, he's already 10 so I just want to do anything so he can live longer.

Raw chicken bones are rubbery, and break in chunks. The risk is similar to a chunk of kibble scratching he throat. When cooked, bones splinter into sharp edges, and causes issues. It should be supervised to make sure they eat it properly.

With a proper diet balance, you can feed nothing but meat, bone, and organs. Organs are an essential part of the raw diet, in smaller amounts.

In a raw diet, much is learned by watching their poop. Chalky poop means too much bone, liquid poop usually is too much organs, soft poop would be too much meat. You learn to balance the diet based on that, it is a very individual thing.